bun add @sigma-auth/better-auth-plugin better-auth

import { betterAuth } from "better-auth";
import { sigmaAuth } from "@sigma-auth/better-auth-plugin";

export const auth = betterAuth({
  plugins: [
    sigmaAuth({
      tokenpassUrl: "http://localhost:21000"
    })
  ]
});

import { createAuthClient } from "better-auth/client";
import { sigmaAuthClient } from "@sigma-auth/better-auth-plugin/client";

export const authClient = createAuthClient({
  plugins: [sigmaAuthClient()]
});

// Sign in with TokenPass
await authClient.signIn.sigma();

// Redirect user to TokenPass
const params = new URLSearchParams({
  redirect: 'https://yourapp.com/callback',
  host: 'yourapp.com',
  scopes: 'sign'
});

window.location.href = `http://localhost:21000/auth?${params}`;

// On your callback page
const url = new URL(window.location.href);
const signature = url.searchParams.get('signature');
const address = url.searchParams.get('address');
const message = url.searchParams.get('message');

// Verify the signature on your server
const verified = await verifySignature({ signature, address, message });

import { BSM } from '@bsv/sdk';

function verifySignature({ signature, address, message }) {
  return BSM.verify(message, signature, address);
}

import { useState } from 'react';

export function useTokenPass() {
  const [user, setUser] = useState(null);

  const signIn = () => {
    const params = new URLSearchParams({
      redirect: window.location.origin + '/auth/callback',
      host: window.location.host,
      scopes: 'sign'
    });
    window.location.href = `http://localhost:21000/auth?${params}`;
  };

  const handleCallback = async (searchParams) => {
    const signature = searchParams.get('signature');
    const address = searchParams.get('address');

    // Verify with your backend
    const res = await fetch('/api/auth/verify', {
      method: 'POST',
      body: JSON.stringify({ signature, address })
    });

    if (res.ok) {
      setUser(await res.json());
    }
  };

  return { user, signIn, handleCallback };
}